Sweet corn hybrid svsk4540 and parents thereof

ABSTRACT

The invention provides seed and plants of corn hybrid SVSK4540 and the parent lines thereof. The invention thus relates to the plants, seeds, and tissue cultures of corn hybrid SVSK4540 and the parent lines thereof and to methods for producing a corn plant produced by crossing such plants with themselves or with another corn plant, such as a plant of another genotype. The invention further relates to seeds and plants produced by such crossing. The invention further relates to parts of such plants, including the fruit and gametes of such plants.

FIELD OF THE INVENTION

The present invention relates to the field of plant breeding and, morespecifically, to the development of corn hybrid SVSK4540, inbred cornline SHY-6S16-7790LL, and inbred corn line SHY-6S15-2102XW.

BACKGROUND OF THE INVENTION

The goal of vegetable breeding is to combine various desirable traits ina single variety/hybrid. Such desirable traits may include any traitdeemed beneficial or desirable by a grower and/or consumer, includinggreater yield, resistance to insects or disease, tolerance toenvironmental stress, and nutritional value.

Breeding techniques take advantage of a plant's method of pollination.There are two general methods of pollination: a plant self-pollinates ifpollen from one flower is transferred to the same or another flower ofthe same plant or plant variety. A plant cross-pollinates if pollencomes to it from a flower of a different plant variety.

Plants that have been self-pollinated and selected for type over manygenerations become homozygous at almost all genetic loci and produce auniform population of true breeding progeny, a homozygous plant. A crossbetween two such homozygous plants of different genotypes produces auniform population of hybrid plants that are heterozygous for manygenetic loci. Conversely, a cross of two plants each heterozygous at anumber of loci produces a population of hybrid plants that differgenetically and are not uniform. The resulting non-uniformity makesperformance unpredictable.

The development of uniform varieties requires the development ofhomozygous inbred plants, the crossing of these inbred plants, and theevaluation of the crosses. Pedigree breeding and recurrent selection areexamples of breeding methods that have been used to develop inbredplants from breeding populations. Those breeding methods combine thegenetic backgrounds from two or more plants or various other broad-basedsources into breeding pools from which new lines and hybrids derivedtherefrom are developed by selfing and selection of desired phenotypes.The new lines and hybrids are evaluated to determine which of those havecommercial potential.

SUMMARY OF THE INVENTION

In one aspect, the present invention provides a corn plant of the hybriddesignated SVSK4540, corn line SHY-6S16-7790LL, or corn lineSHY-6S15-2102XW. Also provided are corn plants having all thephysiological and morphological characteristics of such a plant. Partsof these corn plants are also provided, for example, including pollen,an ovule, an embryo, a seed, a scion, a rootstock, a fruit, and a cellof the plant.

In another aspect of the invention, a plant of corn hybrid SVSK4540,corn line SHY-6S16-7790LL, and/or corn line SHY-6S15-2102XW comprisingan added heritable trait is provided. The heritable trait may comprise agenetic locus that is, for example, a dominant or recessive allele. Inone embodiment of the invention, a plant of corn hybrid SVSK4540, cornline SHY-6S16-7790LL, and/or corn line SHY-6S15-2102XW is defined ascomprising a single locus conversion. In specific embodiments of theinvention, an added genetic locus confers one or more traits such as,for example, herbicide tolerance, insect resistance, disease resistance,and modified carbohydrate metabolism. In further embodiments, the traitmay be conferred by a naturally occurring gene introduced into thegenome of a line by backcrossing, a natural or induced mutation, or atransgene introduced through genetic transformation techniques into theplant or a progenitor of any previous generation thereof. Whenintroduced through transformation, a genetic locus may comprise one ormore genes integrated at a single chromosomal location.

In some embodiments, a single locus conversion includes one or moresite-specific changes to the plant genome, such as, without limitation,one or more nucleotide modifications, deletions, or insertions. A singlelocus may comprise one or more genes or nucleotides integrated ormutated at a single chromosomal location. In one embodiment, a singlelocus conversion may be introduced by a genetic engineering technique,methods of which include, for example, genome editing with engineerednucleases (GEEN). Engineered nucleases include, but are not limited to,Cas endonucleases; zinc finger nucleases (ZFNs); transcriptionactivator-like effector nucleases (TALENs); engineered meganucleases,also known as homing endonucleases; and other endonucleases for DNA orRNA-guided genome editing that are well-known to the skilled artisan.

The invention also concerns the seed of corn hybrid SVSK4540, corn lineSHY-6S16-7790LL, and/or corn line SHY-6S15-2102XW. The corn seed of theinvention may be provided as an essentially homogeneous population ofcorn seed of corn hybrid SVSK4540, corn line SHY-6S16-7790LL, and/orcorn line SHY-6S15-2102XW. Essentially homogeneous populations of seedare generally free from substantial numbers of other seed. Therefore,seed of hybrid SVSK4540, corn line SHY-6S16-7790LL, and/or corn lineSHY-6S15-2102XW may be defined as forming at least about 97% of thetotal seed, including at least about 98%, 99% or more of the seed. Theseed population may be separately grown to provide an essentiallyhomogeneous population of corn plants designated SVSK4540, corn lineSHY-6S16-7790LL, and/or corn line SHY-6S15-2102XW.

In yet another aspect of the invention, a tissue culture of regenerablecells of a corn plant of hybrid SVSK4540, corn line SHY-6S16-7790LL,and/or corn line SHY-6S15-2102XW is provided. The tissue culture willpreferably be capable of regenerating corn plants capable of expressingall of the physiological and morphological characteristics of thestarting plant and of regenerating plants having substantially the samegenotype as the starting plant. Examples of some of the physiologicaland morphological characteristics of the hybrid SVSK4540, corn lineSHY-6S16-7790LL, and/or corn line SHY-6S15-2102XW include those traitsset forth in the tables herein. The regenerable cells in such tissuecultures may be derived, for example, from embryos, meristems,cotyledons, pollen, leaves, anthers, roots, root tips, pistils, flowers,seeds, stalks, silks, tassels, kernels, ears, cobs, and husks. Stillfurther, the present invention provides corn plants regenerated from atissue culture of the invention, the plants having all the physiologicaland morphological characteristics of hybrid SVSK4540, corn lineSHY-6S16-7790LL, and/or corn line SHY-6S15-2102XW.

In still yet another aspect of the invention, processes are provided forproducing corn seeds, plants, and fruit, which processes generallycomprise crossing a first parent corn plant with a second parent cornplant, wherein at least one of the first or second parent corn plants isa plant of corn line SHY-6S16-7790LL or corn line SHY-6S15-2102XW. Theseprocesses may be further exemplified as processes for preparing hybridcorn seed or plants, wherein a first corn plant is crossed with a secondcorn plant of a different, distinct genotype to provide a hybrid thathas, as one of its parents, a plant of corn line SHY-6S16-7790LL or cornline SHY-6S15-2102XW. In these processes, crossing will result in theproduction of seed. The seed production occurs regardless of whether theseed is collected or not.

In one embodiment of the invention, the first step in “crossing”comprises planting seeds of a first and second parent corn plant, oftenin proximity so that pollination will occur for example, mediated byinsect vectors. Alternatively, pollen can be transferred manually. Wherethe plant is self-pollinated, pollination may occur without the need fordirect human intervention other than plant cultivation. For hybridcrosses, it may be beneficial to detassel or otherwise emasculate theparent used as a female.

A second step may comprise cultivating or growing the seeds of first andsecond parent corn plants into mature plants. A third step may comprisepreventing self-pollination of the plants, such as by detasseling orother means.

A fourth step for a hybrid cross may comprise cross-pollination betweenthe first and second parent corn plants. Yet another step comprisesharvesting the seeds from at least one of the parent corn plants. Theharvested seed can be grown to produce a corn plant or hybrid cornplant.

The present invention also provides the corn seeds and plants producedby a process that comprises crossing a first parent corn plant with asecond parent corn plant, wherein at least one of the first or secondparent corn plants is a plant of corn hybrid SVSK4540, corn lineSHY-6S16-7790LL, and/or corn line SHY-6S15-2102XW. In one embodiment ofthe invention, corn seed and plants produced by the process are firstgeneration (F₁) hybrid corn seed and plants produced by crossing a plantin accordance with the invention with another, distinct plant. Thepresent invention further contemplates plant parts of such an F₁ hybridcorn plant and methods of use thereof. Therefore, certain exemplaryembodiments of the invention provide an F₁ hybrid corn plant and seedthereof.

In still yet another aspect, the present invention provides a method ofproducing a plant derived from hybrid SVSK4540, corn lineSHY-6S16-7790LL, and/or corn line SHY-6S15-2102XW, the method comprisingthe steps of: (a) preparing a progeny plant derived from hybridSVSK4540, corn line SHY-6S16-7790LL, and/or corn line SHY-6S15-2102XW,wherein said preparing comprises crossing a plant of the hybridSVSK4540, corn line SHY-6S16-7790LL, and/or corn line SHY-6S15-2102XWwith a second plant; and (b) crossing the progeny plant with itself or asecond plant to produce a seed of a progeny plant of a subsequentgeneration. In further embodiments, the method may additionallycomprise: (c) growing a progeny plant of a subsequent generation fromsaid seed of a progeny plant of a subsequent generation and crossing theprogeny plant of a subsequent generation with itself or a second plant;and repeating the steps for an additional 3-10 generations to produce aplant derived from hybrid SVSK4540, corn line SHY-6S16-7790LL, and/orcorn line SHY-6S15-2102XW. The plant derived from hybrid SVSK4540, cornline SHY-6S16-7790LL, and/or corn line SHY-6S15-2102XW may be an inbredline, and the aforementioned repeated crossing steps may be defined ascomprising sufficient inbreeding to produce the inbred line. In themethod, it may be desirable to select particular plants resulting fromstep (c) for continued crossing according to steps (b) and (c). Byselecting plants having one or more desirable traits, a plant derivedfrom hybrid SVSK4540, corn line SHY-6S16-7790LL, and/or corn lineSHY-6S15-2102XW is obtained which possesses some of the desirable traitsof the line/hybrid as well as potentially other selected traits.

In certain embodiments, the present invention provides a method ofproducing food or feed comprising: (a) obtaining a plant of corn hybridSVSK4540, corn line SHY-6S16-7790LL, and/or corn line SHY-6S15-2102XW,wherein the plant has been cultivated to maturity, and (b) collecting atleast one corn from the plant.

In still yet another aspect of the invention, the genetic complement ofcorn hybrid SVSK4540, corn line SHY-6S16-7790LL, and/or corn lineSHY-6S15-2102XW is provided. The phrase “genetic complement” is used torefer to the aggregate of nucleotide sequences, the expression of whichsequences defines the phenotype of, in the present case, a corn plant,or a cell or tissue of that plant. A genetic complement thus representsthe genetic makeup of a cell, tissue, or plant, and a hybrid geneticcomplement represents the genetic make-up of a hybrid cell, tissue, orplant. The invention thus provides corn plant cells that have a geneticcomplement in accordance with the corn plant cells disclosed herein andseeds and plants containing such cells.

Plant genetic complements may be assessed by genetic marker profiles andby the expression of phenotypic traits that are characteristic of theexpression of the genetic complement, e.g., isozyme typing profiles. Itis understood that hybrid SVSK4540, corn line SHY-6S16-7790LL, and/orcorn line SHY-6S15-2102XW could be identified by any of the manywell-known techniques such as, for example, Simple Sequence LengthPolymorphisms (SSLPs) (Williams et al., Nucleic Acids Res., 18:6531-6535, 1990), Randomly Amplified Polymorphic DNAs (RAPDs), DNAAmplification Fingerprinting (DAF), Sequence Characterized AmplifiedRegions (SCARs), Arbitrary Primed Polymerase Chain Reaction (AP-PCR),Amplified Fragment Length Polymorphisms (AFLPs) (EP 534 858,specifically incorporated herein by reference in its entirety), andSingle Nucleotide Polymorphisms (SNPs) (Wang et al., Science,280:1077-1082, 1998).

In still yet another aspect, the present invention provides hybridgenetic complements, as represented by corn plant cells, tissues,plants, and seeds, formed by the combination of a haploid geneticcomplement of a corn plant of the invention with a haploid geneticcomplement of a second corn plant, preferably, another, distinct cornplant. In another aspect, the present invention provides a corn plantregenerated from a tissue culture that comprises a hybrid geneticcomplement of this invention.

Any embodiment discussed herein with respect to one aspect of theinvention applies to other aspects of the invention as well, unlessspecifically noted.

The term “about” is used to indicate that a value includes the standarddeviation of the mean for the device or method being employed todetermine the value. The use of the term “or” in the claims is used tomean “and/or” unless explicitly indicated to refer to alternatives onlyor the alternatives are mutually exclusive. When used in conjunctionwith the word “comprising” or other open language in the claims, thewords “a” and “an” denote “one or more,” unless specifically notedotherwise. The terms “comprise,” “have” and “include” are open-endedlinking verbs. Any forms or tenses of one or more of these verbs, suchas “comprises,” “comprising,” “has,” “having,” “includes” and“including,” are also open-ended. For example, any method that“comprises,” “has” or “includes” one or more steps is not limited topossessing only those one or more steps and also covers other unlistedsteps. Similarly, any plant that “comprises,” “has” or “includes” one ormore traits is not limited to possessing only those one or more traitsand covers other unlisted traits.

Other objects, features, and advantages of the present invention willbecome apparent from the following detailed description. It should beunderstood, however, that the detailed description and any specificexamples provided, while indicating specific embodiments of theinvention, are given by way of illustration only, since various changesand modifications within the spirit and scope of the invention willbecome apparent to those skilled in the art from this detaileddescription.

DETAILED DESCRIPTION OF THE INVENTION

The invention provides methods and compositions relating to plants,seeds, and derivatives of corn hybrid SVSK4540, corn lineSHY-6S16-7790LL, and corn line SHY-6S15-2102XW.

Corn hybrid SVSK4540, also known as 19-6S-SHY-4540 and 52863, fullymatures in 76 days and develops a plant that produces strong roots.

A. Origin and Breeding History of Corn Hybrid SVSK4540

The parents of hybrid SVSK4540 are corn line SHY-6S16-7790LL and cornline SHY-6S15-2102XW. The parent lines are uniform and stable, as is ahybrid produced therefrom. A small percentage of variants can occurwithin commercially acceptable limits for almost any characteristicduring the course of repeated multiplication. However no variants areexpected.

B. Physiological and Morphological Characteristics of Corn HybridSVSK4540, Corn Line SHY-6S16-7790LL, and Corn Line SHY-6S15-2102XW

In accordance with one aspect of the present invention, there areprovided plants having the physiological and morphologicalcharacteristics of corn hybrid SVSK4540 and the parent lines thereof. Adescription of the physiological and morphological characteristics ofsuch plants is presented in Tables 1-3.

TABLE 1 Physiological and Morphological Characteristics of Corn HybridSVSK4540 CHARACTERISTIC SVSK4540 BASIN Type sweet sweet Maturity in theRegion of Best Adaptability region where developed in the U.S.A.northwest northwest emergence to 50% of plants in silk 53 days 53 days1027.23 heat units 1018.23 heat units emergence to 50% of plants inpollen 53 days 51 days 1013.03 heat units 987.3 heat units 10% to 90%pollen shed 5 days 5 days 116.75 heat units 135.33 heat units 50% silkto optimum edible quality 19 days 22 days 427.63 heat units 383.13 heatunits Plant plant height (to tassel tip) (cm) avg: 195.47 avg: 201.36std dev: 7.1781 std dev: 7.346 sample size: 15 sample size: 15 earheight (to base of top ear node) (cm) avg: 59.06 avg: 58.71 std dev:7.375 std dev: 6.215 sample size: 15 sample size: 15 length of top earinternode (cm) avg: 15.20 avg: 15.62 std dev: 1.263 std dev: 0.9597sample size: 15 sample size: 15 average number of tillers avg: 0.97 avg:1.53 std dev: 0.6322 std dev: 0.6309 sample size: 15 sample size: 15average number of ears per stalk avg: 2.00 avg: 2.33 std dev: 0.2582 stddev: 0.433 sample size: 15 sample size: 15 anthocyanin of brace rootsabsent absent Leaf width of ear node leaf (cm) avg: 10.36 avg: 9.23 stddev: 0.5304 std dev: 0.4202 sample size: 15 sample size: 15 length ofear node leaf (cm) avg: 72.62 avg: 73.66 std dev: 3.8621 std dev: 3.345sample size: 15 sample size: 15 number of leaves above top ear avg: 6.47avg: 6.57 std dev: 0.5408 std dev: 0.615 sample size: 15 sample size: 15leaf angle (second leaf above ear at  52.5  70.5 anthesis to stalk aboveleaf) (degrees) color (Munsell Color Chart Code) 5GY 3/4 5GY 3/4 leafsheath pubescence (scale from 1 6 8 (none) to 9 (like peach fuzz))marginal waves (scale from 1 (none) to 9 7 6 (many)) longitudinalcreases (scale from 1 (none) 7 6 to 9 (many)) Tassel number of primarylateral branches avg: 28.00 avg: 25.57 std dev: 3.5987 std dev: 3.109sample size: 15 sample size: 15 branch angle from central spike(degrees) avg: 52.8 avg: 67.40 std dev: 9.6388 std dev: 9.741 samplesize: 15 sample size: 15 tassel length (top leaf collar to tassel tip)avg: 41.56 avg: 37.92 (cm) std dev: 2.3731 std dev: 1.867 sample size:15 sample size: 15 pollen shed (scale from 0 (male sterile) to 8 6 9(heavy shed)) anther color (Munsell Color Chart Code) 2.5GY 8/6 2.5GY7/6 glume color (Munsell Color Chart Code) 2.5GY 8/6 5GY 6/6 bar glumes(glume bands) present present Ear silk color (unhusked) (Munsell Color2.5GY 8/6 2.5GY 8/6 Chart Code) (3 days after emergence) fresh huskcolor (unhusked) (Munsell 2.5GY 8/6 5GY 5/6 Color Chart Code) (25 daysafter 50% silking) husk tightness (unhusked) (scale from 1 4 9 (veryloose) to 9 (very tight)) husk extension (unhusked) (at harvest) mediumshort ear length (husked) (cm) avg: 22.75 avg: 24.97 std dev: 0.9267 stddev: 1.262 sample size: 15 sample size: 15 ear diameter at mid-point(husked) (mm) avg: 48.24 avg: 46.11 std dev: 1.3816 std dev: 1.99 samplesize: 15 sample size: 15 ear weight (husked) (g) avg: 288.74 avg: 289.63std dev: 22.1935 std dev: 28.987 sample size: 15 sample size: 15 numberof kernel rows (husked) avg: 18.93 avg: 17.44 std dev: 1.5935 std dev:1.239 sample size: 15 sample size: 15 kernel rows (husked) distinctdistinct row alignment (husked) slightly curved straight shank length(husked) (cm) avg: 16.92 avg: 15.39 std dev: 2.7703 std dev: 2.265sample size: 15 sample size: 15 ear taper (husked) average extreme Cobcob diameter at mid-point (mm) avg: 33.04 avg: 29.68 std dev: 2.1309 stddev: 2.337 sample size: 15 sample size: 15 cob color (Munsell ColorChart Code) 2.5GY 8/4 2.5GY 8/2 Agronomic Traits pre-anthesis brittlesnapping 0% 0% pre-anthesis root lodging 0% 0% These are typical values.Values may vary due to environment. Other values that are substantiallyequivalent are within the scope of the invention.

TABLE 2 Physiological and Morphological Characteristics of Corn LineSHY-6S16-7790LL CHARACTERISTIC SHY-6S16-7790LL FLORIDA 32 Type sweetsweet Maturity in the Region of Best Adaptability region where developedin the U.S.A. northwest northwest emergence to 50% of plants in silk 53days 57 days 1174.73 heat units 1258.53 heat units emergence to 50% ofplants in pollen 50 days 52 days 1116.73 heat units 1146.4 heat units10% to 90% pollen shed 9 days 17 days 214.85 heat units 404.1 heat units50% silk to optimum edible quality 18 days 16 days 410.73 heat units384.20 heat units Plant plant height (to tassel tip) (cm) avg: 99.51avg: 137.70 std dev: 11.22 std dev: 25.1146 sample size: 15 sample size:15 ear height (to base of top ear node) (cm) avg: 22.97 avg: 32.00 stddev: 5.7623 std dev: 5.5355 sample size: 15 sample size: 15 length oftop ear internode (cm) avg: 8.52 avg: 8.79 std dev: 1.591 std dev:2.0733 sample size: 15 sample size: 15 average number of tillers avg:0.77 avg: 2.57 std dev: 0.6592 std dev: 1.4521 sample size: 15 samplesize: 15 average number of ears per stalk avg: 1.84 avg: 2.43 std dev:0.4824 std dev: 0.7574 sample size: 15 sample size: 15 anthocyanin ofbrace roots absent absent Leaf width of ear node leaf (cm) avg: 8.53avg: 6.94 std dev: 0.9199 std dev: 0.6561 sample size: 15 sample size:15 length of ear node leaf (cm) avg: 54.51 avg: 70.40 std dev: 8.292 stddev: 3.7515 sample size: 15 sample size: 15 number of leaves above topear avg: 5.9 avg: 4.3 std dev: 0.6802 std dev: 0.4491 sample size: 15sample size: 15 leaf angle (second leaf above ear at 56  29  anthesis tostalk above leaf) (degrees) color (Munsell Color Chart Code) 7.5GY 3/25GY 3/4 leaf sheath pubescence (scale from 1 8 2 (none) to 9 (like peachfuzz)) marginal waves (scale from 1 (none) to 9 4 5 (many)) longitudinalcreases (scale from 1 (none) 6 8 to 9 (many)) Tassel number of primarylateral branches avg: 18.67 avg: 11.83 std dev: 3.9996 std dev: 3.3413sample size: 15 sample size: 15 branch angle from central spike(degrees) avg: 52.27 avg: 51.74 std dev: 12.4722 std dev: 12.086 samplesize: 15 sample size: 15 tassel length (top leaf collar to tassel tip)avg: 26.83 avg: 41.94 (cm) std dev: 2.2886 std dev: 3.4245 sample size:15 sample size: 15 pollen shed (scale from 0 (male sterile) to 7 8 9(heavy shed)) anther color (Munsell Color Chart Code) 2.5GY 8/6 2.5GY8/6 glume color (Munsell Color Chart Code) 5GY 5/4 5GY 5/4 bar glumes(glume bands) present present Ear silk color (unhusked) (Munsell Color2.5GY 8/6 2.5GY 8/6 Chart Code) (3 days after emergence) fresh huskcolor (unhusked) (Munsell 5GY 7/8 5GY 7/6 Color Chart Code) (25 daysafter 50% silking) husk tightness (unhusked) (scale from 1 6 6 (veryloose) to 9 (very tight)) husk extension (unhusked) (at harvest) mediummedium ear length (husked) (cm) avg: 16.02 avg: 14.03 std dev: 0.9742std dev: 1.7307 sample size: 15 sample size: 15 ear diameter atmid-point (husked) (mm) avg: 38.86 avg: 31.29 std dev: 2.9329 std dev:2.3818 sample size: 15 sample size: 15 ear weight (husked) (g) avg:125.80 avg: 52.87 std dev: 48.3493 std dev: 17.3655 sample size: 15sample size: 15 number of kernel rows (husked) avg: 16.27 avg: 13.13 stddev: 1.2044 std dev: 1.5108 sample size: 15 sample size: 15 kernel rows(husked) indistinct indistinct row alignment (husked) slightly curvedslightly curved shank length (husked) (cm) avg: 12.26 avg: 22.58 stddev: 2.2215 std dev: 2.5998 sample size: 15 sample size: 15 ear taper(husked) average average Cob cob diameter at mid-point (mm) avg: 28.61avg: 24.02 std dev: 1.9224 std dev: 1.7385 sample size: 15 sample size:15 cob color (Munsell Color Chart Code) 2.5GY 8/4 2.5GY 8/4 AgronomicTraits pre-anthesis brittle snapping 0% 0% pre-anthesis root lodging 0%0% These are typical values. Values may vary due to environment. Othervalues that are substantially equivalent are within the scope of theinvention.

TABLE 3 Physiological and Morphological Characteristics of Corn LineSHY-6S15-2102XW CHARACTERISTIC SHY-6S15-2102XW FLORIDA 32 Type sweetsweet Maturity in the Region of Best Adaptability region where developedin the U.S.A. northwest northwest emergence to 50% of plants in silk 63days 59 days 1347.68 heat units 1288.65 heat units emergence to 50% ofplants in pollen 60 days 54 days 1296.58 heat units 1179.25 heat units10% to 90% pollen shed 7 days 9 days 161.15 heat units 211.68 heat units50% silk to optimum edible quality 22 days 21 days 502.23 heat units480.93 heat units Plant plant height (to tassel tip) (cm) avg: 182.97avg: 130.18 std dev: 11.2771 std dev: 7.4972 sample size: 15 samplesize: 15 ear height (to base of top ear node) (cm) avg: 63.68 avg: 40.75std dev: 8.8729 std dev: 4.9133 sample size: 15 sample size: 15 lengthof top ear internode (cm) avg: 14.83 avg: 11.32 std dev: 2.5313 std dev:1.3849 sample size: 15 sample size: 15 average number of tillers avg:1.80 avg: 3.93 std dev: 0.884 std dev: 1.3583 sample size: 15 samplesize: 15 average number of ears per stalk avg: 1.90 avg: 2.70 std dev:0.4709 std dev: 0.6036 sample size: 15 sample size: 15 anthocyanin ofbrace roots absent absent Leaf width of ear node leaf (cm) avg: 8.18avg: 7.01 std dev: 0.4296 std dev: 0.4963 sample size: 15 sample size:15 length of ear node leaf (cm) avg: 84.76 avg: 72.79 std dev: 4.2946std dev: 3.8640 sample size: 15 sample size: 15 number of leaves abovetop ear avg: 5.07 avg: 4.50 std dev: 0.7482 std dev: 0.5182 sample size:15 sample size: 15 leaf angle (second leaf above ear at 27  47  anthesisto stalk above leaf) (degrees) color (Munsell Color Chart Code) 5GY 4/45GY 4/4 leaf sheath pubescence (scale from 1 3 4 (none) to 9 (like peachfuzz)) marginal waves (scale from 1 (none) to 9 7 7 (many)) longitudinalcreases (scale from 1 (none) 7 7 to 9 (many)) Tassel number of primarylateral branches avg: 22.67 avg: 11.73 std dev: 2.6869 std dev: 1.7651sample size: 15 sample size: 15 branch angle from central spike(degrees) avg: 41 avg: 36 std dev: 9.6666 std dev: 11.1580 sample size:15 sample size: 15 tassel length (top leaf collar to tassel tip) avg:45.87 avg: 39.17 (cm) std dev: 4.5551 std dev: 2.7682 sample size: 15sample size: 15 pollen shed (scale from 0 (male sterile) to 6 6 9 (heavyshed)) anther color (Munsell Color Chart Code) 2.5GY 8/6 2.5GY 8/8 glumecolor (Munsell Color Chart Code) 5GY 6/6 5GY 5/4 bar glumes (glumebands) present present Ear silk color (unhusked) (Munsell Color 2.5GY7/6 2.5GY 8/6 Chart Code) (3 days after emergence) fresh husk color(unhusked) (Munsell 2.5GY 6/6 2.5GY 7/8 Color Chart Code) (25 days after50% silking) husk tightness (unhusked) (scale from 1 7 7 (very loose) to9 (very tight)) husk extension (unhusked) (at harvest) very long longear length (husked) (cm) avg: 18.56 avg: 15.33 std dev: 1.8504 std dev:2.8550 sample size: 15 sample size: 15 ear diameter at mid-point(husked) (mm) avg: 32.86 avg: 35.06 std dev: 1.8785 std dev: 4.6044sample size: 15 sample size: 15 ear weight (husked) (g) avg: 83.07 avg:62.77 std dev: 13.8537 std dev: 25.8194 sample size: 15 sample size: 15number of kernel rows (husked) avg: 14.80 avg: 15.37 std dev: 1.7857 stddev: 1.6180 sample size: 15 sample size: 15 kernel rows (husked)indistinct indistinct row alignment (husked) spiral slightly curvedshank length (husked) (cm) avg: 21.38 avg: 21.35 std dev: 3.8351 stddev: 5.1643 sample size: 15 sample size: 15 ear taper (husked) extremeextreme Cob cob diameter at mid-point (mm) avg: 25.42 avg: 25.16 stddev: 1.4426 std dev: 3.5713 sample size: 15 sample size: 15 cob color(Munsell Color Chart Code) 2.5GY 8/4 2.5GY 8/4 Agronomic Traitspre-anthesis brittle snapping 0% 0% pre-anthesis root lodging 0% 0%These are typical values. Values may vary due to environment. Othervalues that are substantially equivalent are within the scope of theinvention.

C. Breeding Corn Plants

One aspect of the current invention concerns methods for producing seedof corn hybrid SVSK4540 involving crossing corn lines SHY-6S16-7790LLand SHY-6S15-2102XW. Alternatively, in other embodiments of theinvention, hybrid SVSK4540, corn line SHY-6S16-7790LL, or corn lineSHY-6S15-2102XW may be crossed with itself or with any second plant.Such methods can be used for propagation of hybrid SVSK4540, corn lineSHY-6S16-7790LL, and/or the corn line SHY-6S15-2102XW or can be used toproduce plants that are derived from hybrid SVSK4540, corn lineSHY-6S16-7790LL, and/or the corn line SHY-6S15-2102XW. Plants derivedfrom hybrid SVSK4540, corn line SHY-6S16-7790LL, and/or the corn lineSHY-6S15-2102XW may be used, in certain embodiments, for the developmentof new corn varieties.

The development of new varieties using one or more starting varieties iswell known in the art. In accordance with the invention, novel varietiesmay be created by crossing a plant of the invention followed by multiplegenerations of breeding according to such well-known methods. Newvarieties may be created by crossing with any second plant. In selectingsuch a second plant to cross for the purpose of developing novel lines,it may be desired to choose those plants which either themselves exhibitone or more selected desirable characteristics or which exhibit thedesired characteristic(s) when in hybrid combination. Once initialcrosses have been made, inbreeding and selection take place to producenew varieties. For development of a uniform line, often five or moregenerations of selfing and selection are involved.

Uniform lines of new varieties may also be developed by way ofdouble-haploids. This technique allows the creation of true breedinglines without the need for multiple generations of selfing andselection. In this manner true breeding lines can be produced in aslittle as one generation. Haploid induction systems have been developedfor various plants to produce haploid tissues, plants and seeds. Thehaploid induction system can produce haploid plants from any genotype bycrossing with an inducer line. Inducer lines and methods for obtaininghaploid plants are known in the art.

Haploid embryos may be produced, for example, from microspores, pollen,anther cultures, or ovary cultures. The haploid embryos may then bedoubled autonomously, or by chemical treatments (e.g. colchicinetreatment). Alternatively, haploid embryos may be grown into haploidplants and treated to induce chromosome doubling. In either case,fertile homozygous plants are obtained. In accordance with theinvention, any of such techniques may be used in connection with a plantof the invention and progeny thereof to achieve a homozygous line.

Backcrossing can also be used to improve an inbred plant. Backcrossingtransfers a specific desirable trait from one inbred or non-inbredsource to an inbred that lacks that trait. This can be accomplished, forexample, by first crossing a superior inbred (A) (recurrent parent) to adonor inbred (non-recurrent parent), which carries the appropriate locusor loci for the trait in question. The progeny of this cross are thenmated back to the superior recurrent parent (A) followed by selection inthe resultant progeny for the desired trait to be transferred from thenon-recurrent parent. After five or more backcross generations withselection for the desired trait, the progeny have the characteristicbeing transferred, but are like the superior parent for most or almostall other loci. The last backcross generation would be selfed to givepure breeding progeny for the trait being transferred.

The plants of the present invention are particularly well suited for thedevelopment of new lines based on the elite nature of the geneticbackground of the plants. In selecting a second plant to cross withSVSK4540, corn line SHY-6S16-7790LL, and/or corn line SHY-6S15-2102XWfor the purpose of developing novel corn lines, it will typically bepreferred to choose those plants which either themselves exhibit one ormore selected desirable characteristics or which exhibit the desiredcharacteristic(s) when in hybrid combination. Examples of desirabletraits may include, in specific embodiments, male sterility, herbicideresistance, resistance for bacterial, fungal, or viral disease, insectresistance, male fertility, sugar content, and enhanced nutritionalquality.

D. Further Embodiments of the Invention

In certain aspects of the invention, plants described herein areprovided modified to include at least a first desired heritable trait.Such plants may, in one embodiment, be developed by a plant breedingtechnique called backcrossing or by genetic engineering, whereinessentially all of the morphological and physiological characteristicsof a variety are recovered in addition to a genetic locus transferredinto the plant via the backcrossing or genetic engineering technique.The term single locus converted plant as used herein refers to thosecorn plants which are developed by a plant breeding technique calledbackcrossing or by genetic engineering, wherein essentially all of themorphological and physiological characteristics of a variety arerecovered or conserved in addition to the single locus introduced intothe variety via the backcrossing or genetic engineering technique,respectively. By essentially all of the morphological and physiologicalcharacteristics, it is meant that the characteristics of a plant arerecovered or conserved that are otherwise present when compared in thesame environment, other than an occasional variant trait that mightarise during backcrossing, introduction of a transgene, or applicationof a genetic engineering technique.

Backcrossing methods can be used with the present invention to improveor introduce a characteristic into the present variety. The parentalcorn plant which contributes the locus for the desired characteristic istermed the nonrecurrent or donor parent. This terminology refers to thefact that the nonrecurrent parent is used one time in the backcrossprotocol and therefore does not recur. The parental corn plant to whichthe locus or loci from the nonrecurrent parent are transferred is knownas the recurrent parent as it is used for several rounds in thebackcrossing protocol.

In a typical backcross protocol, the original variety of interest(recurrent parent) is crossed to a second variety (nonrecurrent parent)that carries the single locus of interest to be transferred. Theresulting progeny from this cross are then crossed again to therecurrent parent and the process is repeated until a corn plant isobtained wherein essentially all of the morphological and physiologicalcharacteristics of the recurrent parent are recovered in the convertedplant, in addition to the single transferred locus from the nonrecurrentparent.

The selection of a suitable recurrent parent is an important step for asuccessful backcrossing procedure. The goal of a backcross protocol isto alter or substitute a single trait or characteristic in the originalvariety. To accomplish this, a single locus of the recurrent variety ismodified or substituted with the desired locus from the nonrecurrentparent, while retaining essentially all of the rest of the desiredgenetic, and therefore the desired physiological and morphologicalconstitution of the original variety. The choice of the particularnonrecurrent parent will depend on the purpose of the backcross; one ofthe major purposes is to add some commercially desirable trait to theplant. The exact backcrossing protocol will depend on the characteristicor trait being altered and the genetic distance between the recurrentand nonrecurrent parents. Although backcrossing methods are simplifiedwhen the characteristic being transferred is a dominant allele, arecessive allele, or an additive allele (between recessive anddominant), may also be transferred. In this instance it may be necessaryto introduce a test of the progeny to determine if the desiredcharacteristic has been successfully transferred.

In one embodiment, progeny corn plants of a backcross in which a plantdescribed herein is the recurrent parent comprise (i) the desired traitfrom the non-recurrent parent and (ii) all of the physiological andmorphological characteristics of corn the recurrent parent as determinedat the 5% significance level when grown in the same environmentalconditions.

New varieties can also be developed from more than two parents. Thetechnique, known as modified backcrossing, uses different recurrentparents during the backcrossing. Modified backcrossing may be used toreplace the original recurrent parent with a variety having certain moredesirable characteristics or multiple parents may be used to obtaindifferent desirable characteristics from each.

With the development of molecular markers associated with particulartraits, it is possible to add additional traits into an established germline, such as represented here, with the end result being substantiallythe same base germplasm with the addition of a new trait or traits.Molecular breeding, as described in Moose and Mumm, 2008 (PlantPhysiol., 147: 969-977), for example, and elsewhere, provides amechanism for integrating single or multiple traits or QTL into an eliteline. This molecular breeding-facilitated movement of a trait or traitsinto an elite line may encompass incorporation of a particular genomicfragment associated with a particular trait of interest into the eliteline by the mechanism of identification of the integrated genomicfragment with the use of flanking or associated marker assays. In theembodiment represented here, one, two, three or four genomic loci, forexample, may be integrated into an elite line via this methodology. Whenthis elite line containing the additional loci is further crossed withanother parental elite line to produce hybrid offspring, it is possibleto then incorporate at least eight separate additional loci into thehybrid. These additional loci may confer, for example, such traits as adisease resistance or a fruit quality trait. In one embodiment, eachlocus may confer a separate trait. In another embodiment, loci may needto be homozygous and exist in each parent line to confer a trait in thehybrid. In yet another embodiment, multiple loci may be combined toconfer a single robust phenotype of a desired trait.

Many single locus traits have been identified that are not regularlyselected for in the development of a new inbred but that can be improvedby backcrossing techniques. Single locus traits may or may not betransgenic; examples of these traits include, but are not limited to,male sterility, waxy starch, herbicide resistance, resistance tobacterial, fungal, or viral disease, insect resistance, sugar content,male fertility and enhanced nutritional quality. These genes aregenerally inherited through the nucleus, but may be inherited throughthe cytoplasm. Some known exceptions to this are genes for malesterility, some of which are inherited cytoplasmically, but still act asa single locus trait.

Direct selection may be applied where the single locus acts as adominant trait. For this selection process, the progeny of the initialcross are assayed for viral resistance and/or the presence of thecorresponding gene prior to the backcrossing. Selection eliminates anyplants that do not have the desired gene and resistance trait, and onlythose plants that have the trait are used in the subsequent backcross.This process is then repeated for all additional backcross generations.

Selection of corn plants for breeding is not necessarily dependent onthe phenotype of a plant and instead can be based on geneticinvestigations. For example, one can utilize a suitable genetic markerwhich is closely genetically linked to a trait of interest. One of thesemarkers can be used to identify the presence or absence of a trait inthe offspring of a particular cross and can be used in selection ofprogeny for continued breeding. This technique is commonly referred toas marker assisted selection. Any other type of genetic marker or otherassay which is able to identify the relative presence or absence of atrait of interest in a plant can also be useful for breeding purposes.Procedures for marker assisted selection are well known in the art. Suchmethods will be of particular utility in the case of recessive traitsand variable phenotypes, or where conventional assays may be moreexpensive, time consuming or otherwise disadvantageous. In addition,marker assisted selection may be used to identify plants comprisingdesirable genotypes at the seed, seedling, or plant stage, to identifyor assess the purity of a cultivar, to catalog the genetic diversity ofa germplasm collection, and to monitor specific alleles or haplotypeswithin an established cultivar.

Types of genetic markers which could be used in accordance with theinvention include, but are not necessarily limited to, Simple SequenceLength Polymorphisms (SSLPs) (Williams et al., Nucleic Acids Res., 18:6531-6535, 1990), Randomly Amplified Polymorphic DNAs (RAPDs), DNAAmplification Fingerprinting (DAF), Sequence Characterized AmplifiedRegions (SCARs), Arbitrary Primed Polymerase Chain Reaction (AP-PCR),Amplified Fragment Length Polymorphisms (AFLPs) (EP 534 858,specifically incorporated herein by reference in its entirety), andSingle Nucleotide Polymorphisms (SNPs) (Wang et al., Science,280:1077-1082, 1998).

In particular embodiments of the invention, marker assisted selection isused to increase the efficiency of a backcrossing breeding scheme forproducing a corn line comprising a desired trait. This technique iscommonly referred to as marker assisted backcrossing (MABC). Thistechnique is well-known in the art and may involve, for example, the useof three or more levels of selection, including foreground selection toidentity the presence of a desired locus, which may complement orreplace phenotype screening protocols; recombinant selection to minimizelinkage drag; and background selection to maximize recurrent parentgenome recovery.

E. Plants Derived by Genetic Engineering

Various genetic engineering technologies have been developed and may beused by those of skill in the art to introduce traits in plants. Incertain aspects of the claimed invention, traits are introduced intocorn plants via altering or introducing a single genetic locus ortransgene into the genome of a recited variety or progenitor thereof.Methods of genetic engineering to modify, delete, or insert genes andpolynucleotides into the genomic DNA of plants are well-known in theart.

In specific embodiments of the invention, improved corn lines can becreated through the site-specific modification of a plant genome.Methods of genetic engineering include, for example, utilizingsequence-specific nucleases such as zinc-finger nucleases (see, forexample, U.S. Pat. Appl. Pub. No. 2011-0203012); engineered or nativemeganucleases; TALE-endonucleases (see, for example, U.S. Pat. Nos.8,586,363 and 9,181,535); and RNA-guided endonucleases, such as those ofthe CRISPR/Cas systems (see, for example, U.S. Pat. Nos. 8,697,359 and8,771,945 and U.S. Pat. Appl. Pub. No. 2014-0068797). One embodiment ofthe invention thus relates to utilizing a nuclease or any associatedprotein to carry out genome modification. This nuclease could beprovided heterologously within donor template DNA for templated-genomicediting or in a separate molecule or vector. A recombinant DNA constructmay also comprise a sequence encoding one or more guide RNAs to directthe nuclease to the site within the plant genome to be modified. Furthermethods for altering or introducing a single genetic locus include, forexample, utilizing single-stranded oligonucleotides to introduce basepair modifications in a corn plant genome (see, for example Sauer etal., Plant Physiol, 170(4):1917-1928, 2016).

Methods for site-directed alteration or introduction of a single geneticlocus are well-known in the art and include those that utilizesequence-specific nucleases, such as the aforementioned, or complexes ofproteins and guide-RNA that cut genomic DNA to produce a double-strandbreak (DSB) or nick at a genetic locus. As is well-understood in theart, during the process of repairing the DSB or nick introduced by thenuclease enzyme, a donor template, transgene, or expression cassettepolynucleotide may become integrated into the genome at the site of theDSB or nick. The presence of homology arms in the DNA to be integratedmay promote the adoption and targeting of the insertion sequence intothe plant genome during the repair process through homologousrecombination or non-homologous end joining (NHEJ).

In another embodiment of the invention, genetic transformation may beused to insert a selected transgene into a plant of the invention ormay, alternatively, be used for the preparation of transgenes which canbe introduced by backcrossing. Methods for the transformation of plantsthat are well-known to those of skill in the art and applicable to manycrop species include, but are not limited to, electroporation,microprojectile bombardment, Agrobacterium-mediated transformation, anddirect DNA uptake by protoplasts.

To effect transformation by electroporation, one may employ eitherfriable tissues, such as a suspension culture of cells or embryogeniccallus or alternatively one may transform immature embryos or otherorganized tissue directly. In this technique, one would partiallydegrade the cell walls of the chosen cells by exposing them topectin-degrading enzymes (pectolyases) or mechanically wound tissues ina controlled manner.

An efficient method for delivering transforming DNA segments to plantcells is microprojectile bombardment. In this method, particles arecoated with nucleic acids and delivered into cells by a propellingforce. Exemplary particles include those comprised of tungsten,platinum, and, preferably, gold. For the bombardment, cells insuspension are concentrated on filters or solid culture medium.Alternatively, immature embryos or other target cells may be arranged onsolid culture medium. The cells to be bombarded are positioned at anappropriate distance below the macroprojectile stopping plate.

An illustrative embodiment of a method for delivering DNA into plantcells by acceleration is the Biolistics Particle Delivery System, whichcan be used to propel particles coated with DNA or cells through ascreen, such as a stainless steel or Nytex screen, onto a surfacecovered with target cells. The screen disperses the particles so thatthey are not delivered to the recipient cells in large aggregates.Microprojectile bombardment techniques are widely applicable and may beused to transform virtually any plant species.

Agrobacterium-mediated transfer is another widely applicable system forintroducing gene loci into plant cells. An advantage of the technique isthat DNA can be introduced into whole plant tissues, thereby bypassingthe need for regeneration of an intact plant from a protoplast. ModernAgrobacterium transformation vectors are capable of replication in E.coli as well as Agrobacterium, allowing for convenient manipulations(Klee et al., Nat. Biotechnol., 3(7):637-642, 1985). Moreover, recenttechnological advances in vectors for Agrobacterium-mediated genetransfer have improved the arrangement of genes and restriction sites inthe vectors to facilitate the construction of vectors capable ofexpressing various polypeptide coding genes. The vectors described haveconvenient multi-linker regions flanked by a promoter and apolyadenylation site for direct expression of inserted polypeptidecoding genes. Additionally, Agrobacterium containing both armed anddisarmed Ti genes can be used for transformation.

In those plant strains where Agrobacterium-mediated transformation isefficient, it is the method of choice because of the facile and definednature of the gene locus transfer. The use of Agrobacterium-mediatedplant integrating vectors to introduce DNA into plant cells is wellknown in the art (Fraley et al., Nat. Biotechnol., 3:629-635, 1985; U.S.Pat. No. 5,563,055).

Transformation of plant protoplasts also can be achieved using methodsbased on calcium phosphate precipitation, polyethylene glycol treatment,electroporation, and combinations of these treatments (see, e.g.,Potrykus et al., Mol. Gen. Genet., 199:183-188, 1985; Omirulleh et al.,Plant Mol. Biol., 21(3):415-428, 1993; Fromm et al., Nature,312:791-793, 1986; Uchimiya et al., Mol. Gen. Genet., 204:204, 1986;Marcotte et al., Nature, 335:454, 1988). Transformation of plants andexpression of foreign genetic elements is exemplified in Choi et al.(Plant Cell Rep., 13: 344-348, 1994) and Ellul et al. (Theor. Appl.Genet., 107:462-469, 2003).

A number of promoters have utility for plant gene expression for anygene of interest including but not limited to selectable markers,scoreable markers, genes for pest tolerance, disease resistance,nutritional enhancements and any other gene of agronomic interest.Examples of constitutive promoters useful for plant gene expressioninclude, but are not limited to, the cauliflower mosaic virus (CaMV)P-35S promoter, which confers constitutive, high-level expression inmost plant tissues (see, e.g., Odel et al., Nature, 313:810, 1985),including in monocots (see, e.g., Dekeyser et al., Plant Cell, 2:591,1990; Terada and Shimamoto, Mol. Gen. Genet., 220:389, 1990); a tandemlyduplicated version of the CaMV 35S promoter, the enhanced 35S promoter(P-e35S); the nopaline synthase promoter (An et al., Plant Physiol.,88:547, 1988); the octopine synthase promoter (Fromm et al., Plant Cell,1:977, 1989); and the figwort mosaic virus (P-FMV) promoter as describedin U.S. Pat. No. 5,378,619 and an enhanced version of the FMV promoter(P-eFMV) where the promoter sequence of P-FMV is duplicated in tandem;the cauliflower mosaic virus 19S promoter; a sugarcane bacilliform viruspromoter; a commelina yellow mottle virus promoter; and other plant DNAvirus promoters known to express in plant cells.

A variety of plant gene promoters that are regulated in response toenvironmental, hormonal, chemical, and/or developmental signals can alsobe used for expression of an operably linked gene in plant cells,including promoters regulated by (1) heat (Callis et al., PlantPhysiol., 88:965, 1988), (2) light (e.g., pea rbcS-3A promoter,Kuhlemeier et al., Plant Cell, 1:471, 1989; maize rbcS promoter,Schaffner and Sheen, Plant Cell, 3:997, 1991; or chlorophyll a/b-bindingprotein promoter, Simpson et al., EMBO J., 4:2723, 1985), (3) hormones,such as abscisic acid (Marcotte et al., Plant Cell, 1:969, 1989), (4)wounding (e.g., wunl, Siebertz et al., Plant Cell, 1:961, 1989); or (5)chemicals such as methyl jasmonate, salicylic acid, or Safener. It mayalso be advantageous to employ organ-specific promoters (e.g., Roshal etal., EMBO J., 6:1155, 1987; Schernthaner et al., EMBO J., 7:1249, 1988;Bustos et al., Plant Cell, 1:839, 1989).

Exemplary nucleic acids which may be introduced to plants of thisinvention include, for example, DNA sequences or genes from anotherspecies, or even genes or sequences which originate with or are presentin the same species, but are incorporated into recipient cells bygenetic engineering methods rather than classical reproduction orbreeding techniques. However, the term “exogenous” is also intended torefer to genes that are not normally present in the cell beingtransformed, or perhaps simply not present in the form, structure, etc.,as found in the transforming DNA segment or gene, or genes which arenormally present and that one desires to express in a manner thatdiffers from the natural expression pattern, e.g., to over-express.Thus, the term “exogenous” gene or DNA is intended to refer to any geneor DNA segment that is introduced into a recipient cell, regardless ofwhether a similar gene may already be present in such a cell. The typeof DNA included in the exogenous DNA can include DNA which is alreadypresent in the plant cell, DNA from another plant, DNA from a differentorganism, or a DNA generated externally, such as a DNA sequencecontaining an antisense message of a gene, or a DNA sequence encoding asynthetic or modified version of a gene.

Many hundreds if not thousands of different genes are known and couldpotentially be introduced into a corn plant according to the invention.Non-limiting examples of particular genes and corresponding phenotypesone may choose to introduce into a corn plant include one or more genesfor insect tolerance, such as a Bacillus thuringiensis (B.t.) gene, pesttolerance such as genes for fungal disease control, herbicide tolerancesuch as genes conferring glyphosate tolerance and genes for qualityimprovements such as yield, nutritional enhancements, environmental orstress tolerances, or any desirable changes in plant physiology, growth,development, morphology or plant product(s). For example, structuralgenes would include any gene that confers insect tolerance including butnot limited to a Bacillus insect control protein gene as described in WO99/31248, herein incorporated by reference in its entirety, U.S. Pat.No. 5,689,052, herein incorporated by reference in its entirety, U.S.Pat. Nos. 5,500,365 and 5,880,275, herein incorporated by reference intheir entirety. In another embodiment, the structural gene can confertolerance to the herbicide glyphosate as conferred by genes including,but not limited to Agrobacterium strain CP4 glyphosate resistant EPSPSgene (aroA:CP4) as described in U.S. Pat. No. 5,633,435, hereinincorporated by reference in its entirety, or glyphosate oxidoreductasegene (GOX) as described in U.S. Pat. No. 5,463,175, herein incorporatedby reference in its entirety.

Alternatively, the DNA coding sequences can affect these phenotypes byencoding a non-translatable RNA molecule that causes the targetedinhibition of expression of an endogenous gene, for example viaantisense- or cosuppression-mediated mechanisms (see, for example, Birdet al., Biotech. Gen. Engin. Rev., 9:207, 1991). The RNA could also be acatalytic RNA molecule (i.e., a ribozyme) engineered to cleave a desiredendogenous mRNA product (see for example, Gibson and Shillito, Mol.Biotech., 7:125, 1997). Thus, any gene which produces a protein or mRNAwhich expresses a phenotype or morphology change of interest is usefulfor the practice of the present invention.

F. Male Sterility

Examples of genes conferring male sterility include those disclosed inU.S. Pat. Nos. 3,861,709, 3,710,511, 4,654,465, 5,625,132, and4,727,219, each of the disclosures of which are specificallyincorporated herein by reference in their entirety. Male sterility genescan increase the efficiency with which hybrids are made, in that theyeliminate the need to physically emasculate the corn plant used as afemale in a given cross.

Where one desires to employ male-sterility systems with a corn plant inaccordance with the invention, it may be beneficial to also utilize oneor more male-fertility restorer genes. For example, where cytoplasmicmale sterility (CMS) is used, hybrid seed production requires threeinbred lines: (1) a cytoplasmically male-sterile line having a CMScytoplasm; (2) a fertile inbred with normal cytoplasm, which is isogenicwith the CMS line for nuclear genes (“maintainer line”); and (3) adistinct, fertile inbred with normal cytoplasm, carrying a fertilityrestoring gene (“restorer” line). The CMS line is propagated bypollination with the maintainer line, with all of the progeny being malesterile, as the CMS cytoplasm is derived from the female parent. Thesemale sterile plants can then be efficiently employed as the femaleparent in hybrid crosses with the restorer line, without the need forphysical emasculation of the male reproductive parts of the femaleparent.

The presence of a male-fertility restorer gene results in the productionof fully fertile F₁ hybrid progeny. If no restorer gene is present inthe male parent, male-sterile hybrids are obtained. Such hybrids areuseful where the vegetative tissue of the corn plant is utilized, e.g.,for silage, but in most cases, the seeds will be deemed the mostvaluable portion of the crop, so fertility of the hybrids in these cropsmust be restored. Therefore, one aspect of the current inventionconcerns a corn plant of the invention comprising a genetic locuscapable of restoring male fertility in an otherwise male-sterile plant.Examples of male-sterility genes and corresponding restorers which couldbe employed with the plants of the invention are well known to those ofskill in the art of plant breeding and are disclosed in, for instance,U.S. Pat. Nos. 5,530,191; 5,689,041; 5,741,684; and 5,684,242, thedisclosures of which are each specifically incorporated herein byreference in their entirety.

G. Herbicide Resistance

Numerous herbicide resistance genes are known and may be employed withthe invention. An example is a gene conferring resistance to a herbicidethat inhibits the growing point or meristem, such as an imidazalinone ora sulfonylurea. Exemplary genes in this category code for mutant ALS andAHAS enzyme as described, for example, by Lee et al., EMBO J., 7:1241,1988; Gleen et al., Plant Molec. Biology, 18:1185-1187, 1992; and Mikiet al., Theor. Appl. Genet., 80:449, 1990.

Resistance genes for glyphosate (resistance conferred by mutant5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) and aroA genes,respectively), and hygromycin B phosphotransferase, and to otherphosphono compounds such as glufosinate (phosphinothricin acetyltransferase (PAT) and Streptomyces hygroscopicus phosphinothricin-acetyltransferase (bar) genes) may also be used. See, for example, U.S. Pat.No. 4,940,835 to Shah et al., which discloses the nucleotide sequence ofa form of EPSPS which can confer glyphosate resistance. A DNA moleculeencoding a mutant aroA gene can be obtained under ATCC accession number39256, and the nucleotide sequence of the mutant gene is disclosed inU.S. Pat. No. 4,769,061 to Comai. A hygromycin B phosphotransferase genefrom E. coli that confers resistance to glyphosate in tobacco callus andplants is described in Penaloza-Vazquez et al. (Plant Cell Reports,14:482-487, 1995). European patent application No. 0 333 033 to Kumadaet al., and U.S. Pat. No. 4,975,374 to Goodman et al., disclosenucleotide sequences of glutamine synthetase genes which conferresistance to herbicides such as L-phosphinothricin. The nucleotidesequence of a phosphinothricin-acetyltransferase gene is provided inEuropean application No. 0 242 246 to Leemans et al. DeGreef et al.,(Biotechnology, 7:61, 1989), describe the production of transgenicplants that express chimeric bar genes coding for phosphinothricinacetyl transferase activity. Exemplary of genes conferring resistance tophenoxy propionic acids and cyclohexanediones, such as sethoxydim andhaloxyfop are the Acct-S1, Accl-S2 and Acct-S3 genes described byMarshall et al., (Theor. Appl. Genet., 83:4:35, 1992).

Genes conferring resistance to a herbicide that inhibits photosynthesisare also known, such as a triazine (psbA and gs+ genes) and abenzonitrile (nitrilase gene). Przibilla et al., (Plant Cell, 3:169,1991), describe the transformation of Chlamydomonas with plasmidsencoding mutant psbA genes. Nucleotide sequences for nitrilase genes aredisclosed in U.S. Pat. No. 4,810,648 to Stalker, and DNA moleculescontaining these genes are available under ATCC Accession Nos. 53435,67441, and 67442. Cloning and expression of DNA coding for a glutathioneS-transferase is described by Hayes et al., (Biochem. J., 285(Pt1):173-180, 1992). Protoporphyrinogen oxidase (PPO) is the target of thePPO-inhibitor class of herbicides; a PPO-inhibitor resistant PPO genewas recently identified in Amaranthus tuberculatus (Patzoldt et al.,PNAS, 103(33):12329-2334, 2006). The herbicide methyl viologen inhibitsCO₂ assimilation. Foyer et al. (Plant Physiol., 109:1047-1057, 1995)describe a plant overexpressing glutathione reductase (GR) which isresistant to methyl viologen treatment.

Siminszky (Phytochemistry Reviews, 5:445-458, 2006) describes plantcytochrome P450-mediated detoxification of multiple, chemicallyunrelated classes of herbicides.

H. Waxy Starch

The waxy characteristic is an example of a recessive trait. In thisexample, the progeny resulting from the first backcross generation (BC1)must be grown and selfed. A test is then run on the selfed seed from theBC1 plant to determine which BC1 plants carried the recessive gene forthe waxy trait. In other recessive traits additional progeny testing,for example growing additional generations such as the BC1S1, may berequired to determine which plants carry the recessive gene.

I. Disease Resistance

Plant defenses are often activated by specific interaction between theproduct of a disease resistance gene (R) in the plant and the product ofa corresponding avirulence (Avr) gene in the pathogen. A plant line canbe transformed with a cloned resistance gene to engineer plants that areresistant to specific pathogen strains. See, for example, Jones et al.,Science, 266:7891, 1994 (cloning of the tomato Cf-9 gene for resistanceto Cladosporium fulvum); Martin et al., Science, 262: 1432, 1993 (tomatoPto gene for resistance to Pseudomonas syringae pv.); and Mindrinos etal., Cell, 78(6):1089-1099, 1994 (Arabidopsis RPS2 gene for resistanceto Pseudomonas syringae).

A viral-invasive protein or a complex toxin derived therefrom may alsobe used for viral disease resistance. For example, the accumulation ofviral coat proteins in transformed plant cells imparts resistance toviral infection and/or disease development effected by the virus fromwhich the coat protein gene is derived, as well as by related viruses.See Beachy et al., (Ann. Rev. Phytopathol., 28:451, 1990). Coatprotein-mediated resistance has been conferred upon transformed plantsagainst alfalfa mosaic virus, cucumber mosaic virus, tobacco streakvirus, potato virus X, potato virus Y, tobacco etch virus, tobaccorattle virus and tobacco mosaic virus. Id.

A virus-specific antibody may also be used. See, for example,Tavladoraki et al., (Nature, 366:469, 1993), who show that transgenicplants expressing recombinant antibody genes are protected from virusattack. Additional means of inducing whole-plant resistance to apathogen include modulation of the systemic acquired resistance (SAR) orpathogenesis related (PR) genes, for example genes homologous to theArabidopsis thaliana NIM1/NPRYSAI1, and/or by increasing salicylic acidproduction (Ryals et al., Plant Cell, 8:1809-1819, 1996).

Logemann et al., (Biotechnology, 10:305, 1992), for example, disclosetransgenic plants expressing a barley ribosome-inactivating gene have anincreased resistance to fungal disease. Plant defensins may be used toprovide resistance to fungal pathogens (Thomma et al., Planta,216:193-202, 2002). Other examples of fungal disease resistance areprovided in U.S. Pat. Nos. 6,653,280; 6,573,361; 6,506,962; 6,316,407;6,215,048; 5,516,671; 5,773,696; 6,121,436; 6,316,407; and 6,506,962.

J. Insect Resistance

One example of an insect resistance gene includes a Bacillusthuringiensis (Bt) protein, a derivative thereof or a syntheticpolypeptide modeled thereon. See, for example, Geiser et al., (Gene,48:109-118, 1986), who disclose the cloning and nucleotide sequence of aBt δ-endotoxin gene. Moreover, DNA molecules encoding δ-endotoxin genescan be purchased from the American Type Culture Collection, Manassas,Virginia, for example, under ATCC Accession Nos. 40098, 67136, 31995 and31998. Another example is a lectin. See, for example, Van Damme et al.,(Plant Molec. Biol., 24:25, 1994), who disclose the nucleotide sequencesof several Clivia miniata mannose-binding lectin genes. Avitamin-binding protein may also be used, such as avidin. See PCTapplication US93/06487, the contents of which are hereby incorporated byreference. This application teaches the use of avidin and avidinhomologues as larvicides against insect pests.

Yet another insect resistance gene is an enzyme inhibitor, for example,a protease or proteinase inhibitor or an amylase inhibitor. See, forexample, Abe et al., (J. Biol. Chem., 262:16793, 1987) (nucleotidesequence of rice cysteine proteinase inhibitor), Huub et al., (PlantMolec. Biol., 21:985, 1993) (nucleotide sequence of cDNA encodingtobacco proteinase inhibitor I), and Sumitani et al., (Biosci. Biotech.Biochem., 57:1243, 1993) (nucleotide sequence of Streptomycesnitrosporeus α-amylase inhibitor).

An insect-specific hormone or pheromone may also be used. See, forexample, the disclosure by Hammock et al., (Nature, 344:458, 1990), ofbaculovirus expression of cloned juvenile hormone esterase, aninactivator of juvenile hormone, Gade and Goldsworthy (Eds.Physiological System in Insects, Elsevier Academic Press, Burlington, MA, 2007), describing allostatins and their potential use in pestcontrol; and Palli et al., (Vitam. Horm., 73:59-100, 2005), disclosinguse of ecdysteroid and ecdysteroid receptor in agriculture. The diuretichormone receptor (DHR) was identified in Price et al., (Insect Mol.Biol., 13:469-480, 2004) as a candidate target of insecticides.

Still other examples include an insect-specific antibody or animmunotoxin derived therefrom and a developmental-arrestive protein. SeeTaylor et al., (Seventh Int'l Symposium on Molecular Plant-MicrobeInteractions, Edinburgh, Scotland, Abstract W97, 1994), who describedenzymatic inactivation in transgenic tobacco via production ofsingle-chain antibody fragments.

Nematode resistance has been described, for example, in U.S. Pat. No.6,228,992 and bacterial disease resistance in U.S. Pat. No. 5,516,671.

K. Modified Fatty Acid, Phytate, and Carbohydrate Metabolism

Genes may be used conferring modified fatty acid metabolism. Forexample, stearyl-ACP desaturase genes may be used. See Knutzon et al.,(Proc. Natl. Acad. Sci. USA, 89:2624, 1992). Various fatty aciddesaturases have also been described, such as a Saccharomyces cerevisiaeOLE1 gene encoding Δ9 fatty acid desaturase, an enzyme which forms themonounsaturated palmitoleic (16:1) and oleic (18:1) fatty acids frompalmitoyl (16:0) or stearoyl (18:0) CoA (McDonough et al., J. Biol.Chem., 267(9):5931-5936, 1992); a gene encoding a stearoyl-acyl carrierprotein delta-9 desaturase from castor (Fox et al., Proc. Natl. Acad.Sci. USA, 90(6):2486-2490, 1993); Δ6- and Δ12-desaturases from thecyanobacteria Synechocystis responsible for the conversion of linoleicacid (18:2) to gamma-linolenic acid (18:3 gamma) (Reddy et al., PlantMol. Biol., 22(2):293-300, 1993); a gene from Arabidopsis thaliana thatencodes an omega-3 desaturase (Arondel et al., Science,258(5086):1353-1355 1992); plant Δ9-desaturases (PCT Application Publ.No. WO 91/13972) and soybean and Brassica Δ15 desaturases (EuropeanPatent Application Publ. No. EP 0616644).

Phytate metabolism may also be modified by introduction of aphytase-encoding gene to enhance breakdown of phytate, adding more freephosphate to the transformed plant. For example, see Van Hartingsveldtet al., (Gene, 127:87, 1993), for a disclosure of the nucleotidesequence of an Aspergillus niger phytase gene. In corn, this, forexample, could be accomplished by cloning and then reintroducing DNAassociated with the single allele which is responsible for corn mutantscharacterized by low levels of phytic acid. See Raboy et al., PlantPhysiol., 124(1):355-368, 1990.

A number of genes are known that may be used to alter carbohydratemetabolism. For example, plants may be transformed with a gene codingfor an enzyme that alters the branching pattern of starch. See Shirozaet al., (J. Bacteriol., 170:810, 1988) (nucleotide sequence ofStreptococcus mutans fructosyltransferase gene), Steinmetz et al., (Mol.Gen. Genet., 20:220, 1985) (nucleotide sequence of Bacillus subtilislevansucrase gene), Pen et al., (Biotechnology, 10:292, 1992)(production of transgenic plants that express Bacillus licheniformisα-amylase), Elliot et al., (Plant Molec. Biol., 21:515, 1993)(nucleotide sequences of tomato invertase genes), Sergaard et al., (J.Biol. Chem., 268:22480, 1993) (site-directed mutagenesis of barleyα-amylase gene), and Fisher et al., (Plant Physiol., 102:1045, 1993)(maize endosperm starch branching enzyme II). The Z10 gene encoding a 10kD zein storage protein from maize may also be used to alter thequantities of 10 kD zein in the cells relative to other components(Kirihara et al., Gene, 71(2):359-370, 1988).

U.S. Pat. No. 6,930,225 describes maize cellulose synthase genes andmethods of use thereof.

L. Resistance to Abiotic Stress

Abiotic stress includes dehydration or other osmotic stress, salinity,high or low light intensity, high or low temperatures, submergence,exposure to heavy metals, and oxidative stress.Delta-pyrroline-5-carboxylate synthetase (PSCS) from mothbean has beenused to provide protection against general osmotic stress.Mannitol-1-phosphate dehydrogenase (mt1D) from E. coli has been used toprovide protection against drought and salinity. Choline oxidase (codAfrom Arthrobactor globiformis) can protect against cold and salt. E.coli choline dehydrogenase (betA) provides protection against salt.Additional protection from cold can be provided by omega-3-fatty aciddesaturase (fad7) from Arabidopsis thaliana. Trehalose-6-phosphatesynthase and levan sucrase (SacB) from yeast and Bacillus subtilis,respectively, can provide protection against drought (summarized fromAnnex II Genetic Engineering for Abiotic Stress Tolerance in Plants,Consultative Group On International Agricultural Research TechnicalAdvisory Committee). Overexpression of superoxide dismutase can be usedto protect against superoxides, as described in U.S. Pat. No. 5,538,878to Thomas et al.

M. Additional Traits

Additional traits can be introduced into a corn variety of the presentinvention. A non-limiting example of such a trait is a coding sequencewhich decreases RNA and/or protein levels. The decreased RNA and/orprotein levels may be achieved through RNAi methods, such as thosedescribed in U.S. Pat. No. 6,506,559 to Fire and Mellow.

Another trait that may find use with the corn variety of the inventionis a sequence which allows for site-specific recombination. Examples ofsuch sequences include the FRT sequence, used with the FLP recombinase(Zhu and Sadowski, J. Biol. Chem., 270:23044-23054, 1995); and the LOXsequence, used with CRE recombinase (Sauer, Mol. Cell. Biol.,7:2087-2096, 1987). The recombinase genes can be encoded at any locationwithin the genome of the corn plant, and are active in the hemizygousstate.

It may also be desirable to make corn plants more tolerant to or moreeasily transformed with Agrobacterium tumefaciens. Expression of p53 andiap, two baculovirus cell-death suppressor genes, inhibited tissuenecrosis and DNA cleavage. Additional targets can include plant-encodedproteins that interact with the Agrobacterium Vir genes; enzymesinvolved in plant cell wall formation; and histones, histoneacetyltransferases and histone deacetylases (reviewed in Gelvin,Microbiology & Mol. Biol. Reviews, 67:16-37, 2003).

In addition to the modification of oil, fatty acid or phytate contentdescribed above, it may additionally be beneficial to modify the amountsor levels of other compounds. For example, the amount or composition ofantioxidants can be altered. See, for example, U.S. Pat. Nos. 6,787,618and 7,154,029 and International Patent Appl. Pub. No. WO 00/68393, whichdisclose the manipulation of antioxidant levels, and InternationalPatent Appl. Pub. No. WO 03/082899, which discloses the manipulation ofan antioxidant biosynthetic pathway.

Additionally, seed amino acid content may be manipulated. U.S. Pat. No.5,850,016 and International Patent Appl. Pub. No. WO 99/40209 disclosethe alteration of the amino acid compositions of seeds. U.S. Pat. Nos.6,080,913 and 6,127,600 disclose methods of increasing accumulation ofessential amino acids in seeds.

U.S. Pat. No. 5,559,223 describes synthetic storage proteins in whichthe levels of essential amino acids can be manipulated. InternationalPatent Appl. Pub. No. WO 99/29882 discloses methods for altering aminoacid content of proteins. International Patent Appl. Pub. No. WO98/20133 describes proteins with enhanced levels of essential aminoacids. International Patent Appl. Pub. No. WO 98/56935 and U.S. Pat.Nos. 6,346,403, 6,441,274 and 6,664,445 disclose plant amino acidbiosynthetic enzymes. International Patent Appl. Pub. No. WO 98/45458describes synthetic seed proteins having a higher percentage ofessential amino acids than wild-type.

U.S. Pat. No. 5,633,436 discloses plants comprising a higher content ofsulfur-containing amino acids; U.S. Pat. No. 5,885,801 discloses plantscomprising a high threonine content; U.S. Pat. No. 5,885,802 disclosesplants comprising a high methionine content; U.S. Pat. No. 5,912,414discloses plants comprising a high methionine content; U.S. Pat. No.5,990,389 discloses plants comprising a high lysine content; U.S. Pat.No. 6,459,019 discloses plants comprising an increased lysine andthreonine content; International Patent Appl. Pub. No. WO 98/42831discloses plants comprising a high lysine content; International PatentAppl. Pub. No. WO 96/01905 discloses plants comprising a high threoninecontent; and International Patent Appl. Pub. No. WO 95/15392 disclosesplants comprising a high lysine content.

N. Definitions

In the description and tables herein, a number of terms are used. Inorder to provide a clear and consistent understanding of thespecification and claims, the following definitions are provided:

Allele: Any of one or more alternative forms of a gene locus, all ofwhich alleles relate to one trait or characteristic. In a diploid cellor organism, the two alleles of a given gene occupy corresponding locion a pair of homologous chromosomes.

Backcrossing: A process in which a breeder repeatedly crosses hybridprogeny, for example a first generation hybrid (F₁), back to one of theparents of the hybrid progeny. Backcrossing can be used to introduce oneor more single locus conversions from one genetic background intoanother.

-   -   Barren Plants: Plants that are barren, i.e., lack an ear with        grain or have an ear with only a few scattered kernels.    -   Cg: Colletotrichum graminicola rating. Rating times 10 is        approximately equal to percent total plant infection.    -   CLN: Corn Lethal Necrosis (combination of Maize chlorotic mottle        virus and Maize dwarf mosaic virus) rating. Numerical ratings        are based on a severity scale where 1=most resistant to        9=susceptible.    -   Cn: Corynebacterium nebraskense rating. Rating times 10 is        approximately equal to percent total plant infection.    -   Crossing: The mating of two parent plants.    -   Cross-pollination: Fertilization by the union of two gametes        from different plants.    -   Cz: Cercospora zeae-maydis rating. Rating times 10 is        approximately equal to percent total plant infection.    -   Dgg: Diatraea grandiosella girdling rating (values are percent        plants girdled and stalk lodged).    -   Diploid: A cell or organism having two sets of chromosomes.    -   Dropped Ears: Ears that have fallen from the plant to the        ground.    -   Dsp: Diabrotica species root ratings (1=least affected to        9=severe pruning).    -   Ear-Attitude: The attitude or position of the ear at harvest        scored as upright, horizontal, or pendant.    -   Ear-Cob Color: The color of the cob, scored as white, pink, red,        or brown.    -   Ear-Cob Diameter: The average diameter of the cob measured at        the midpoint.    -   Ear-Cob Strength: A measure of mechanical strength of the cobs        to breakage, scored as strong or weak.    -   Ear-Diameter: The average diameter of the ear at its midpoint.    -   Ear-Dry Husk Color: The color of the husks at harvest scored as        buff, red, or purple.    -   Ear-Fresh Husk Color: The color of the husks 1 to 2 weeks after        pollination scored as green, red, or purple.    -   Ear-Husk Bract: The length of an average husk leaf scored as        short, medium, or long.    -   Ear-Husk Cover: The average distance from the tip of the ear to        the tip of the husks, minimum value no less than zero.    -   Ear-Husk Opening: An evaluation of husk tightness at harvest        scored as tight, intermediate, or open.    -   Ear-Length: The average length of the ear.    -   Ear-Number Per Stalk: The average number of ears per plant.    -   Ear-Shank Internodes: The average number of internodes on the        ear shank.    -   Ear-Shank Length: The average length of the ear shank.    -   Ear-Shelling Percent: The average of the shelled grain weight        divided by the sum of the shelled grain weight and cob weight        for a single ear.    -   Ear-Silk Color: The color of the silk observed 2 to 3 days after        silk emergence scored as green-yellow, yellow, pink, red, or        purple.    -   Ear-Taper (Shape): The taper or shape of the ear scored as        conical, semi-conical, or cylindrical.    -   Ear-Weight: The average weight of an ear.    -   Early Stand: The percent of plants that emerge from the ground        as determined in the early spring.    -   Emasculate: The removal of plant male sex organs or the        inactivation of the organs with a cytoplasmic or nuclear genetic        factor or a chemical agent conferring male sterility.    -   Enzymes: Molecules which can act as catalysts in biological        reactions.    -   ER: Ear rot rating (values approximate percent ear rotted).    -   F₁ Hybrid: The first generation progeny of the cross of two        nonisogenic plants.    -   Final Stand Count: The number of plants just prior to harvest.    -   GDUs: Growing degree units which are calculated by the Barger        Method, where the heat units for a 24-h period are calculated as        GDUs=[(Maximum daily temperature+Minimum daily        temperature)/2]−50. The highest maximum daily temperature used        is 86° F. and the lowest minimum temperature used is 50° F.    -   GDUs to Shed: The number of growing degree units (GDUs) or heat        units required for a variety to have approximately 50% of the        plants shedding pollen as measured from time of planting. GDUs        to shed is determined by summing the individual GDU daily values        from planting date to the date of 50% pollen shed.    -   GDUs to Silk: The number of growing degree units for a variety        to have approximately 50% of the plants with silk emergence as        measured from time of planting. GDUs to silk is determined by        summing the individual GDU daily values from planting date to        the date of 50% silking.    -   Genetic Complement: An aggregate of nucleotide sequences, the        expression of which sequences defines the phenotype in corn        plants, or components of plants including cells or tissue.    -   Genotype: The genetic constitution of a cell or organism.    -   Haploid: A cell or organism having one set of the two sets of        chromosomes in a diploid.    -   Hc2: Helminthosporium carbonum race 2 rating. Rating times 10 is        approximately equal to percent total plant infection.    -   Hc3: Helminthosporium carbonum race 3 rating. Rating times 10 is        approximately equal to percent total plant infection.    -   Hm: Helminthosporium maydis race 0 rating. Rating times 10 is        approximately equal to percent total plant infection.    -   Ht1: Helminthosporium turcicum race 1 rating. Rating times 10 is        approximately equal to percent total plant infection.    -   Ht2: Helminthosporium turcicum race 2 rating. Rating times 10 is        approximately equal to percent total plant infection.    -   HtG: Chlorotic-lesion type resistance. “+” indicates the        presence of Ht chlorotic-lesion type resistance; “−” indicates        absence of Ht chlorotic-lesion type resistance; and “+1-”        indicates segregation of Ht chlorotic-lesion type resistance.        Rating times 10 is approximately equal to percent total plant        infection.    -   Kernel-Aleurone Color: The color of the aleurone scored as        white, pink, tan, brown, bronze, red, purple, pale purple,        colorless, or variegated.    -   Kernel-Cap Color: The color of the kernel cap observed at dry        stage, scored as white, lemon-yellow, yellow, or orange.    -   Kernel-Endosperm Color: The color of the endosperm scored as        white, pale yellow, or yellow.    -   Kernel-Endosperm Type: The type of endosperm scored as normal,        waxy, or opaque.    -   Kernel-Grade: The percent of kernels that are classified as        rounds.    -   Kernel-Length: The average distance from the cap of the kernel        to the pedicel.    -   Kernel-Number Per Row: The average number of kernels in a single        row.    -   Kernel-Pericarp Color: The color of the pericarp scored as        colorless, red-white crown, tan, bronze, brown, light red,        cherry red, or variegated.    -   Kernel-Row Direction: The direction of the kernel rows on the        ear scored as straight, slightly curved, spiral, or indistinct        (scattered).    -   Kernel-Row Number: The average number of rows of kernels on a        single ear.    -   Kernel-Side Color: The color of the kernel side observed at the        dry stage, scored as white, pale yellow, yellow, orange, red, or        brown.    -   Kernel-Thickness: The distance across the narrow side of the        kernel.    -   Kernel-Type: The type of kernel scored as dent, flint, or        intermediate.    -   Kernel-Weight: The average weight of a predetermined number of        kernels.    -   Kernel-Width: The distance across the flat side of the kernel.    -   Kz: Kabatiella zeae rating. Rating times 10 is approximately        equal to percent total plant infection.    -   Leaf-Angle: Angle of the upper leaves to the stalk scored as        upright (0 to 30 degrees), intermediate (30 to 60 degrees), or        lax (60 to 90 degrees).    -   Leaf-Color: The color of the leaves 1 to 2 weeks after        pollination scored as light green, medium green, dark green, or        very dark green.    -   Leaf-Length: The average length of the primary ear leaf.    -   Leaf-Longitudinal Creases: A rating of the number of        longitudinal creases on the leaf surface 1 to 2 weeks after        pollination. Creases are scored as absent, few, or many.    -   Leaf-Marginal Waves: A rating of the waviness of the leaf margin        1 to 2 weeks after pollination, rated as none, few, or many.    -   Leaf-Number: The average number of leaves of a mature plant.        Counting begins with the cotyledonary leaf and ends with the        flag leaf.    -   Leaf-Sheath Anthocyanin: A rating of the level of anthocyanin in        the leaf sheath 1 to 2 weeks after pollination, scored as        absent, basal-weak, basal-strong, weak, or strong.    -   Leaf-Sheath Pubescence: A rating of the pubescence of the leaf        sheath. Ratings are taken 1 to 2 weeks after pollination and        scored as light, medium, or heavy.    -   Leaf-Width: The average width of the primary ear leaf measured        at its widest point.    -   Linkage: A phenomenon wherein alleles on the same chromosome        tend to segregate together more often than expected by chance if        their transmission was independent.    -   LSS: Late season standability (values times 10 approximate        percent plants lodged in disease evaluation plots).    -   Marker: A readily detectable phenotype, preferably inherited in        codominant fashion (both alleles at a locus in a diploid        heterozygote are readily detectable), with no environmental        variance component, i.e., heritability of 1.    -   Moisture: The moisture of the grain at harvest.    -   On1: Ostrinia nubilalis 1st brood rating (1=resistant to        9=susceptible).    -   On2: Ostrinia nubilalis 2nd brood rating (1=resistant to        9=susceptible).    -   Phenotype: The detectable characteristics of a cell or organism,        which characteristics are the manifestation of gene expression.    -   Quantitative Trait Loci (QTL): Quantitative trait loci (QTL)        refer to genetic loci that control to some degree numerically        representable traits that are usually continuously distributed.    -   Regeneration: The development of a plant from tissue culture.    -   Relative Maturity: A maturity rating based on regression        analysis. The regression analysis is developed by utilizing        check hybrids and their previously established day rating versus        actual harvest moistures. Harvest moisture on the hybrid in        question is determined and that moisture value is inserted into        the regression equation to yield a relative maturity.    -   Resistance: As used herein, the terms “resistance” and        “tolerance” are used interchangeably to describe plants that        show no symptoms to a specified biotic pest, pathogen, abiotic        influence or environmental condition. These terms are also used        to describe plants showing some symptoms but that are still able        to produce marketable product with an acceptable yield. Some        plants that are referred to as resistant or tolerant are only so        in the sense that they may still produce a crop, even though the        plants are stunted and the yield is reduced.    -   Root Lodging: Root lodging is the percentage of plants that root        lodge. A plant is counted as root lodged if a portion of the        plant leans from the vertical axis by approximately 30 degrees        or more.    -   Royal Horticultural Society (RHS) Color Chart Value: The RHS        Color Chart is a standardized reference which allows accurate        identification of any color. A color's designation on the chart        describes its hue, brightness, and saturation. A color is        precisely named by the RHS Color Chart by identifying the group        name, sheet number, and letter, e.g., Yellow-Orange Group 19A or        Red Group 41B.    -   Seedling Color: Color of leaves at the 6 to 8 leaf stage.    -   Seedling Height: Plant height at the 6 to 8 leaf stage.    -   Seedling Vigor: A visual rating of the amount of vegetative        growth on a 1 to 9 scale, where 1 equals best. The score is        taken when the average entry in a trial is at the fifth leaf        stage.    -   Selection Index: The selection index gives a single measure of        hybrid's worth based on information from multiple traits. One of        the traits that is almost always included is yield. Traits may        be weighted according to the level of importance assigned to        them.    -   Self-Pollination: The transfer of pollen from the anther to the        stigma of the same plant.    -   Single Locus Converted (Conversion) Plant: Plants which are        developed by a plant breeding technique called backcrossing or        genetic engineering of a locus, wherein essentially all of the        morphological and physiological characteristics of a corn        variety are recovered in addition to the characteristics of the        single locus.    -   Sr: Sphacelotheca reiliana rating is actual percent infection.    -   Stalk-Anthocyanin: A rating of the amount of anthocyanin        pigmentation in the stalk. The stalk is rated 1 to 2 weeks after        pollination as absent, basal-weak, basal-strong, weak, or        strong.    -   Stalk-Brace Root Color: The color of the brace roots observed 1        to 2 weeks after pollination as green, red, or purple.    -   Stalk-Diameter: The average diameter of the lowest visible        internode of the stalk.    -   Stalk-Ear Height: The average height of the ear measured from        the ground to the point of attachment of the ear shank of the        top developed ear to the stalk.    -   Stalk-Internode Direction: The direction of the stalk internode        observed after pollination as straight or zigzag.    -   Stalk-Internode Length: The average length of the internode        above the primary ear.    -   Stalk Lodging: The percentage of plants that did stalk lodge.        Plants are counted as stalk lodged if the plant is broken over        or off below the ear.    -   Stalk-Nodes With Brace Roots: The average number of nodes having        brace roots per plant.    -   Stalk-Plant Height: The average height of the plant as measured        from the soil to the tip of the tassel.    -   Stalk-Tillers: The percent of plants that have tillers. A tiller        is defined as a secondary shoot that has developed as a tassel        capable of shedding pollen.    -   Staygreen: Staygreen is a measure of general plant health near        the time of black layer formation (physiological maturity). It        is usually recorded at the time the ear husks of most entries        within a trial have turned a mature color. Scoring is on a 1 to        9 basis where 1 equals best.    -   STR: Stalk rot rating (values represent severity rating of 1=25%        of inoculated internode rotted to 9=entire stalk rotted and        collapsed).    -   Substantially Equivalent: A characteristic that, when compared,        does not show a statistically significant difference (e.g.,        p=0.05) from the mean.    -   SVC: Southeastern Virus Complex (combination of Maize chlorotic        dwarf virus and Maize dwarf mosaic virus) rating; numerical        ratings are based on a severity scale where 1=most resistant to        9=susceptible.    -   Tassel-Anther Color: The color of the anthers at 50% pollen shed        scored as green-yellow, yellow, pink, red, or purple.    -   Tassel-Attitude: The attitude of the tassel after pollination        scored as open or compact.    -   Tassel-Branch Angle: The angle of an average tassel branch to        the main stem of the tassel scored as upright (less than 30        degrees), intermediate (30 to 45 degrees), or lax (greater than        45 degrees).    -   Tassel-Branch Number: The average number of primary tassel        branches.    -   Tassel-Glume Band: The closed anthocyanin band at the base of        the glume scored as present or absent.    -   Tassel-Glume Color: The color of the glumes at 50% shed scored        as green, red, or purple.    -   Tassel-Length: The length of the tassel measured from the base        of the bottom tassel branch to the tassel tip.    -   Tassel-Peduncle Length: The average length of the tassel        peduncle, measured from the base of the flag leaf to the base of        the bottom tassel branch.    -   Tassel-Pollen Shed: A visual rating of pollen shed determined by        tapping the tassel and observing the pollen flow of        approximately five plants per entry. Rated on a 1 to 9 scale        where 9=sterile, 1=most pollen.    -   Tassel-Spike Length: The length of the spike measured from the        base of the top tassel branch to the tassel tip.    -   Test Weight: Weight of the grain in pounds for a given volume        (bushel) adjusted to 15.5% moisture.    -   Tissue Culture: A composition comprising isolated cells of the        same or a different type or a collection of such cells organized        into parts of a plant.    -   Transgene: A genetic locus comprising a sequence which has been        introduced into the genome of a corn plant by transformation or        site-specific modification.    -   Yield: Yield of grain at harvest adjusted to 15.5% moisture.

O. Deposit Information

A deposit of at least 625 seeds of corn line SHY-6S16-7790LL and cornline SHY-6S15-2102XW, disclosed above and recited in the claims, hasbeen made with the Provasoli-Guillard National Center for Marine Algaeand Microbiota (NCMA), 60 Bigelow Drive, East Boothbay, Maine, 04544USA. The date of deposit for those deposited seeds of corn lineSHY-6516-7790LL and corn line SHY-6S15-2102XW is Apr. 18, 2022. Theaccession numbers for those deposited seeds of corn line SHY-6S16-7790LLand corn line SHY-6S15-2102XW are NCMA Accession No. 202204059 and NCMAAccession No. 202204060, respectively. Upon issuance of a patent, allrestrictions upon the deposits will be removed, and the deposits areintended to meet all of the requirements of 37 C.F.R. §§ 1.801-1.809.The deposits have been accepted under the Budapest Treaty and will bemaintained in the depository for a period of 30 years, or 5 years afterthe last request, or for the effective life of the patent, whichever islonger, and will be replaced if necessary during that period.

Although the foregoing invention has been described in some detail byway of illustration and example for purposes of clarity andunderstanding, it will be obvious that certain changes and modificationsmay be practiced within the scope of the invention, as limited only bythe scope of the appended claims.

All references cited herein are hereby expressly incorporated herein byreference.

What is claimed:
 1. A corn plant comprising at least a first set of thechromosomes of corn line SHY-6S16-7790LL or corn line SHY-6S15-2102XW, asample of seed of said lines having been deposited under NCMA AccessionNo. 202204059 and NCMA Accession No. 202204060, respectively.
 2. A cornseed that produces the plant of claim
 1. 3. The plant of claim 1,wherein the plant is a plant of said corn line SHY-6S16-7790LL or cornline SHY-6S15-2102XW.
 4. The plant of claim 1, wherein the plant is aplant of corn hybrid SVSK4540.
 5. The seed of claim 2, wherein the seedis a seed of said corn line SHY-6S16-7790LL or corn lineSHY-6S15-2102XW.
 6. The seed of claim 2, wherein the seed is a seed ofcorn hybrid SVSK4540.
 7. A plant part of the plant of claim 1, whereinthe plant part comprises a cell of said plant.
 8. A corn plant havingall the physiological and morphological characteristics of the plant ofclaim
 1. 9. A tissue culture of regenerable cells of the plant ofclaim
 1. 10. A method of vegetatively propagating the corn plant ofclaim 1, the method comprising the steps of: (a) collecting tissuecapable of being propagated from the plant of claim 1; and (b)propagating a corn plant from said tissue.
 11. A method of introducing atrait into a corn line, the method comprising: (a) utilizing as arecurrent parent the plant of claim 1 by crossing said plant with adonor corn plant that comprises a trait to produce F₁ progeny; (b)selecting an F₁ progeny that comprises the trait; (c) backcrossing theselected F₁ progeny with a plant of the same corn line used as therecurrent parent in step (a) to produce a backcross progeny; (d)selecting a backcross progeny comprising the trait and otherwisecomprising the morphological and physiological characteristics of therecurrent parent corn line used in step (a); and (e) repeating steps (c)and (d) three or more times to produce a selected fourth or higherbackcross progeny.
 12. A corn plant produced by the method of claim 11.13. A method of producing a corn plant comprising an added trait, themethod comprising introducing a transgene conferring the trait into theplant of claim
 1. 14. A corn plant produced by the method of claim 13.15. A corn plant comprising at least a first set of the chromosomes ofcorn line SHY-6S16-7790LL or corn line SHY-6S15-2102XW, a sample of seedof said lines having been deposited under NCMA Accession No. 202204059and NCMA Accession No. 202204060, respectively, further comprising atransgene.
 16. The plant of claim 15, wherein the transgene confers atrait selected from the group consisting of male sterility, herbicidetolerance, insect resistance, pest resistance, disease resistance,modified fatty acid metabolism, environmental stress tolerance, modifiedcarbohydrate metabolism, and modified protein metabolism.
 17. A cornplant comprising at least a first set of the chromosomes of corn lineSHY-6S16-7790LL or corn line SHY-6S15-2102XW, a sample of seed of saidlines having been deposited under NCMA Accession No. 202204059 and NCMAAccession No. 202204060, respectively, further comprising a single locusconversion.
 18. The plant of claim 17, wherein the single locusconversion confers a trait selected from the group consisting of malesterility, herbicide tolerance, insect resistance, pest resistance,disease resistance, modified fatty acid metabolism, environmental stresstolerance, modified carbohydrate metabolism, and modified proteinmetabolism.
 19. A method for producing a seed of a corn plant derivedfrom at least one of corn hybrid SVSK4540, corn line SHY-6S16-7790LL, orcorn line SHY-6S15-2102XW, the method comprising the steps of: (a)crossing the corn plant of claim 1 with itself or a second corn plant;and (b) allowing a seed of a hybrid SVSK4540-, corn lineSHY-6S16-7790LL-, or corn line SHY-6S15-2102XW-derived corn plant toform.
 20. A method of producing a seed of a hybrid SVSK4540-, corn lineSHY-6S16-7790LL-, or corn line SHY-6S15-2102XW-derived corn plant, themethod comprising the steps of: (a) producing a hybrid SVSK4540-, cornline SHY-6S16-7790LL-, or corn line SHY-6S15-2102XW-derived corn plantfrom a seed produced by crossing the corn plant of claim 1 with itselfor a second corn plant; and (b) crossing the hybrid SVSK4540-, corn lineSHY-6S16-7790LL-, or corn line SHY-6S15-2102XW-derived corn plant withitself or a different corn plant to obtain a seed of a further hybridSVSK4540-, corn line SHY-6S16-7790LL-, or corn lineSHY-6S15-2102XW-derived corn plant.
 21. The method of claim 20, themethod further comprising repeating said producing and crossing steps of(a) and (b) using the seed from said step (b) for producing the plantaccording to step (a) for at least one generation to produce a seed ofan additional hybrid SVSK4540-, corn line SHY-6S16-7790LL-, or corn lineSHY-6S15-2102XW-derived corn plant.
 22. A method of producing an ear ofcorn, the method comprising: (a) obtaining the plant of claim 1, whereinthe plant has been cultivated to maturity; and (b) collecting an ear ofcorn from the plant.